At night, many details are hidden in shadow and can not be seen with the naked eye. A good time exposure can bring these things to view but then of course you may end up blowing out the highlights. This is when it is a good time to use HDR technology. With a tripod, I took 5 different time exposures ranging roughly from 1 second to 10. I sandwiched them using the HDR program in Photoshop. It was amazing to see all of the details emerge. I manipulated the color temperature to the cold end of the scale to bring out a feeling of industrialization.
The most difficult part of this endeavour was trying not to get caught while trespassing and not getting mugged! I did get caught but luckily the security man was a photo enthusiast and he let me go with a warning. This is one photo of a series of 12 images of the LA river.